| Author |
Message
|
| cryptonic26 |
 Posted: Fri Jul 04, 2008 6:31 pm Post subject: OPTICS: Generating Parallel (hard) Light from Diffused Light |
 |
|
Forum Freshman
Joined: 22 Jun 2008
Posts: 18
|
I'm trying to find some information regarding the opposite of soft lighting. I believe the term is parallel light, or hard light.... But Google doesn't respond very well to my search terms-- with respect to the information that I am seeking.
To put it simply, I am trying to create a light source where the shadow of any object in front of the source will be hard and sharp (like sunlight shadows), rather than soft and diffused (like fluorescent light shadows).
I prefer to use a soft light source, such as a fluorescent bulb, due to their low cost, even light distribution, and UV properties; However, I'm at a loss to find a source of information regarding the construction of such a lighting device... Any help to be had here? Some terminology correction would be great, some pointers on a common lens apparatus would be ideal. Anything at all would be appreciated! |
|
| Back to top |
|
 |
| KALSTER |
| Posted: Fri Jul 04, 2008 8:39 pm Post subject: |
|
|
Forum Cosmic Wizard
Joined: 08 Sep 2007
Posts: 2082
Location: South Africa
|
Have you searched for fresnel lights? 
_________________
"Gullibility kills" - Carl Sagan |
|
| Back to top |
|
|
| SteveF |
| Posted: Sat Jul 05, 2008 5:28 am Post subject: |
|
|
Forum Bachelors Degree
Joined: 28 May 2007
Posts: 464
Location: NC USA
|
Ā
The normal way is to use a small, intense source of light. Then you send the light through a small aperture and use a simple convex lens to obtain parallel rays.
It can be done, I suppose, using a fluorescent light, but your resultant beam will use only a small fraction of the available light and it will be rather weak. Fluorescent lighting is not a good source for these kind of experiments.
If you use quality detection equipment a weak beam of light may still be adequate.
Ā |
|
| Back to top |
|
|
| cryptonic26 |
| Posted: Tue Jul 08, 2008 11:15 pm Post subject: |
|
|
Forum Freshman
Joined: 22 Jun 2008
Posts: 18
|
thanks for the replies you guys. sorry I havnt responded- been really busy with work.
Anyhow, I'm working on a projector for photo-lithographic processing of photo-emulsion film trough a mask; So weak uv is okay, i'll just have to bump the exposure time significantly.. which is okay if I can get really tight tolerance on the sharpness of the projected mask.
Thanks again |
|
| Back to top |
|
|
|
|
